Beater roll



Feb. 13, 1934. s. MILNE HEATER ROLL Filed July 21, 1933 I w. y

Patented Feb- 13 19 UNITED STATES PATENT OFFICE BEATER ROLL SamuelMilne, Edinburgh, Scotland Application July 21, 1933, Serial No.681,495, and

in Great Britain February 16, 1932 3 Claims. (01. 92-22 As hithertomade, the said segments have been spaced apart fora distance almostequal to half the width of a segment, a disposition which producesuneven'operation of the machine. Each segment has been formed with asingle lifting pocket or cell to promote circulation of the pulp,

. and the small number of the pockets or cells example shown in Fig. 1,that is as applied to a has rendered the circulation of pulp meagre andslow. 7

The object of this invention is to provide an improved construction ofbeating or refining engine, in which the above-named drawbacks areavoided,. and which also produces improved circulation and increasedefiiciency.

According to the invention the basalt lava or like segments are made toa width at their outer part such as to form a practically continuousshell or covering for the roll or other surface, and the segments areprovided with two, three or more lifting pockets or cells, preferablyequally pitched. When the invention is applied to existing engines, thesegments may be substantially T- shaped in cross-section, the stem ofthe T fitting the usual groove in the body of the roller, or otheroperating part, or they may have an undercut groove or grooves on theirinner face. to fit over an undercut rib or ribs-on the roll. Thesegments will usually be cementedin position, as heretofore, and cementwill be placed between the adjoining faces of the segments. Preferably,though not essentially, one of the pockets or cells will be situatedover the joint between the outer parts of the segments.

In the accompanying drawing:-

Figs. 1 and 2 illustrate two forms of the invention as applied to abeating engine, each figure being a cross-sectional elevation of a partof a roll for a beating engine.

Fig. 3 is a plan of a segment as used for a conical refining engine, and

Fig. 4 is a cross-section Fig. 3.

In carrying out the invention according to the on the line 4--4 of rollgrooved as heretofore, for say 25 segments, the segments a are shaped tofit the groove and be cemented therein in the usual way, but that partof the segment standing out of the groove is extended at each side tolie over the rib b between the grooves, the adjacent segments meeting(except for intervening cement c mid-way over such ribs. Thelongitudinal edges of each segment are formed with a concave chamfer aproducing ahalf groove, so that two adjacent segments have a groove dover the joint between them forming a'lifting pocket or cell. In theouter face of each segmentand equally pitched from the said grooves aretwo further grooves d forming further lifting pockets or cells, all the5 pockets being equally pitched around the roll. A convenient size ofgroove is 1" wide, and a convenient pitch of groove is 2".

In carrying out the invention according to another example, as shown inFig. 2, the segments a are made of extended width from the outer to theinner surface, so that the total number of segments for the rollproduces a shell or covering of uniform thickness. Each segment has anundercut (dovetail) groove 2 in its inner face running from end to endwhich fits over a corresponding projection or rib on the roll. "Ifdesired, more than one groove and projection may be provided. By thisconstruction there is less likelihood of the segments breaking when wornso down. I

Any other suitable means of securing the segments to the roll may beemployed. For instance they may be drilled, and held in position byscrewed studs passing into the roll.

In all cases the segments will be cemented in position. I

The bedplate or bedplates may be grooved with any suitable number ofequally pitched grooves.

The invention may be applied to refining. en-

gines of the conical type or disc'type or of any other known type. Whenapplied to aconical type refiner, the segments will be tapered from oneend to the other, and also, if desired, from the top face to the lower.face, as shown in Figs.

3 and 4, whilst when applied to a disc type refiner, the segments willbe tapered from one end to the other only, and some may be shorter thanothers.

By thus providing an increased number of grooves a more complete andmore rapid circulation is obtained and the equal spacing of the grooveswith omission of .the large gaps between the segments ensures improvedbeating with less shock to the roll.

What I claim is:- i 1. In a paper pulp beating engine, refining engine,or the like, a pulp treating element having a peripheral surface ofstone-like abrasive mate-g rial composed of abutting sections, the outersurting portions of the sections.

. 3. In a paper' pulp treating member, a pulp treating element havingits surface entirely covered by a stone-like abrasive material formed insections arranged in abutting relation, each section being formed toprovide lifting pockets over the abutting portions of-the sections andalso having a lifting pocket between said abutting portions of thesections, all of the pockets being relatively shallow and equidistantlyspaced and of like formation, and said element presenting unbrokencontinuous abrading surfaces between the pockets.

. a SAMUEL MILNE.

